ProjectSummary Manyolderadultswithahistoryofcolonpolypscontinuesurveillancecolonoscopiesevery3-5yearsto monitorforrecurrentpolyps,evenafterage75orwheninpoorhealth.Therearenoexplicitguidelinesfor whentostopsurveillance,unlikethereisforwhentostopscreeningforcolorectalcancer(CRC).Currently, approximately3millionsurveillancecolonoscopiesareperformedannuallyintheUS.Thisnumberwill doubletoalmost6millioninthenext6yearsasthepopulationages,ratesofCRCscreeningincrease,and polypdetectionimproves.Atpresent,therearecriticalknowledgegapsthathinderthedevelopmentof effectivestrategiestooptimizesurveillanceuseinolderadults.Mostcritically,themagnitudeofoveruseof surveillanceinthisagingpopulationhasnotbeenfullyquantified,norhavethefactorsthatinfluencepatient andproviderdecision-making.Therefore,theobjectiveofthisstudyistocreateadetailedcharacterization ofsurveillancecolonoscopypracticeinolderadultsandtoidentifycurrentpracticesandmedicaldecision makingaroundsurveillance.Wewillcapitalizeontheunique,NCI-fundedlongitudinalregistryspecifically designedforcolonoscopy,theNewHampshireColonoscopyRegistry(NHCR).NHCRprospectivelycollects dataonnearly100%ofcolonoscopiesperformedinNHandincludesdetailedcolonoscopyinformation(e.g. indication,findings,pathology,andendoscopistfollow-uprecommendations).Specifically,wewilllink patientsinNHCRtoMedicareclaimsdatainordertoperformadetailedassessmentoftheuseof surveillancebylifeexpectancy,identifypatientsmostandleastlikelytobenefitfromsurveillancebasedon surveillancefindingsandlifeexpectancy,andevaluateproviderrecommendationsfornextsurveillance amongolderadults.Wewillalsoconductsemi-structuredinterviewswithpatients,gastroenterologistsand primarycareproviderstoidentifythemulti-levelfactorsinvolvedinthesurveillancedecision-making process.Atthestudyconclusion,wewillhaveadetailedunderstandingofthecurrentpracticeof surveillancecolonoscopyinolderadultswithestimatesofimportantclinicaloutcomesstratifiedbylife expectancy.Nextstepsincluderesearchtodevelopandvalidatemulti-levelinterventionstoreduce inappropriatesurveillancecolonoscopyuse.Ouroverallgoalistomaximizehighvaluecareamongolder adultswhileminimizingrisks.